With less than 10,000 inhabitants Postojna is barely one of the 20 largest towns in Slovenia, but arguably none are more well-known throughout that world (including the capital Ljubljana) than this relatively nondescript settlement in the southwest of the country that wasn't even officially recognise until 1909. The reason of course it not so much the town itself, but the amazing network of karst caves that lie just below its surface. First opened to the public in 1819, the world-famous Postojna Cave is said to have attracted more than 35 million visitors over the past two centuries, with one of its first being Austro-Hungarian Emperor Francis I the year before it opened.

If this were not enough, Postojna is also blessed with another popular sight in its immediate vicinity, the magnificent Predjama Castle located some 11km to the northwest of the town centre. Built in the 13th century and partially situated under enormous natural stone arch, it's not only a fine castle in its own right, but also sits atop another tourist cave and is also associated with several fascinating legends.

While the vast majority of visitors come to Postojna just to see one or both of its star attractions, with three proper hotels and many other guesthouses and private accommodation options located in and around the town, it makes a good base for exploring parts of central Slovenia as well as the Karst region that extends towards the Adriatic Sea and Italy - Trieste actually being closer to Postojna than Ljubljana (35km and 54km away respectively).